On May 16, 7:26*am, kenseto wrote:
On May 15, 10:45*pm, PD wrote:



On May 15, 7:47*pm, kenseto wrote:

On May 15, 5:22*pm, PD wrote:

On May 15, 8:49*am, kenseto wrote:

On May 14, 5:03*pm, PD wrote:

On May 14, 12:53*pm, kenseto wrote:

On May 14, 11:22*am, " wrote:

On 14 mayo, 10:03, kenseto wrote:

On May 13, 6:36 pm, "Simple Simon" wrote:

3. Einstein asserted that the train observer is rushing toward the
light front from the front and receding away from the light front from
the rear.
These assertions means that the light front from the front
will take less transit time to reach the train observer and that the
light front from the rear will take more transit time to reach the
train observer.

Obviously (assuming that the specificity that you omit has the observers and
events at the same times and locations as the classic thought experiment
does).

No I didn't assume anything of the sort. Einstein's assertion implies
that the light front from the front will take less transit time to
reach the train observer and the light front fron the rear will take
longer transit time to reach the train observer. This can only mean
one thing: Einstein's assertion violates the isotropy of the speed of
light in the train.

Once more you show you do not understand English!. Stop lying!

On the contrary, what Einstein said, and everybody else but you
understands, is that the train observer is moving towards the light
signal coming from the front of the train, and that light signal is,
for sure, traveling at c to reach him (as the back light signal is
also doing). Isotropy is never touched here

****ing idiot....the light signal from the front and the rear were
generated at equal distance from the train observer. if the signal
from the front reaches the train observer before the signal from the
rear that means that it takes different transit times for light to
travel equal distance in different directions.

No, the light signals *started* their transit at different times in
the train frame. The transit times are equal. As a consequence, they
arrive at different times.

Hey idiot if the light signals ("started" or "occurred") at different
times in the train frame then these are not the same light signals as
seen by the track observer. Why? Because Einstein stipulated that the
singals occurred simultaneously.

He said no such thing. You do not have his book in front of you, and
your memory is terrible. He said only that the *track observer*
concludes that the strikes are simultaneous, because he has
observations that are consistent with that conclusion.

Hey idiot if the strikes were not simultaneous to begin with how can
the track observer sees them to be simultaneous?

This is where you get stuck. You think you have to *start* from
choosing an assertion: the strikes are either physically simultaneous
or they are not physically simultaneous, but only one or the other.
Then you think you *derive* observations from those assertions.

Hey idiot the gedanken specified that both observers are at equal
distance from the strikes and that the speed of light is isotropic in
the train and the track. These two specifications (stipulations)
demands that the strikes are physcially simultaneous to begin with if
the track observer was to see the strikes to be simultaneous.

These two specifications (stipulations) ALSO demand that the strikes
are not physically simultaneous to begin with if the train observer
sees the strikes to be not simultaneous.

What you do is to pick and choose and say "Well, I'm looking at the
track observer first, and what he says goes. So if HE says the strikes
are simultaneous, then they are physically simultaneous, and then this
dictates what the train observer MUST see." That is, you're letting
one observer determine what the absolute physical reality is, over the
other observer.

Had you started with the train observer instead, the two
specifications (stipulations) would have demanded that the strikes are
NOT physically simultaneous if the train observer sees the strikes to
be not simultaneous. Then you would have used this to force what the
track observer sees.

Einstein's point in the gedanken is that *neither one* sets the
physical reality. The physical reality is that simultaneity is not an
absolute physical attribute of two events. You cannot let one observer
dictate whether two events are physically simultaneous or not, because
both observers have equal say, and they lead to different conclusions
about the simultaneity of the events. In such a case you have to say
that *physical simultaneity* is frame dependent.




It's the other way around in physics. You *start* with the
observations, and you *derive* assertions. The reason you start that
way in physics is that observations are undeniable.

****ing idiot....there is no observation first. There are specified
conditions that control the predicted observations.

That's not true. Fetch the book and read it again. Einstein sets it up
with observations *first*, not specified physical conditions. Your
memory is bad, and the truth is printed in black and white and has
been so for a century.

You are simply wrong on this, Seto, and it's necessary for you to go
back and check facts, rather than denying reality.


Nature controls
what you observe. That control does not belong to your logic.

****ing idiot....the conditions of the gedanken set up by Einstein
control what will be observed.

Ken Seto

*Nature

dictates what *really* happens, whether you expect it or not, or
whether it makes sense or not. That is the purpose of experiment -- to
tell you what *really* happens as a *starting point*. And THEN you
figure out what assertions are consistent with those experimental
results.

In the present case, we *start* with the observations, and by the end
of the gedanken, Einstein shows that the assertion about simultaneity
of the strikes is different than what you might have expected.
Einstein shows that it is NOT the case that the strikes are either
simultaneous or they are not simultaneous. Einstein shows that they
are BOTH simultaneous and not simultaneous, which one being determined
by which reference frame you're in. He goes on to say that it is
*inconsistent with observation* to insist that it is either one or the
other, but not both -- that prejudice must be dispensed with.

Also if you specify
that the strikes were not simultaneous in the train frame you are
already specifying RoS. In that case why did Einstein need to go
through the following bull **** to prove that the train observer will
not see the strikes to be simultaneous: "...he (the train observer) is
hastening towards the beam of light coming from B, whilst he is riding
on ahead of the beam of light coming from A. Hence the observer will
see the beam of light emitted from B earlier than he will see that
emitted from A.."

At NO TIME does
Einstein ever say that the strikes are assumed to be simultaneous, or
stipulated to be simultaneous in some fundamentally real or absolute
way. When you can actually lay your hands on the book you remember
only dimly, I can help you read it for comprehension, sentence by
sentence.

****ing idiot the whole purpose of Einstein's gedanken is to prove
that two original simultaneous strikes are simultaneous in the track
frame because the track observer is not moving wrt the light fronts
and they are not simultaneous in the train frame because the train
observer is moving wrt the light fronts.

No, sir, that is NOT the purpose of the gedanken. The purpose of the
gedanken is precisely what he WROTE is the purpose of the gedanken.
And if you will bother to READ what he WROTE as his explicit purpose,
you will see that purpose written in black and white. In the beginning
of what he WROTE, he explains that his purpose is to pose and answer
the question whether simultaneity is a condition that can be said to
apply to a pair of events regardless of observer. At the end of the
gedanken, he WROTE the answer to the question posed: The answer is NO.
A pair of events that are reallio-trulio simultaneous in one frame are
reallio-trulio non-simultaneous in another frame. THAT is the purpose
of the gedanken, and we know that because that's what he WROTE is the
purpose of the gedanken.

For you to say that the purpose is something other than what he
explicitly said his purpose is, is simply a denial of reality, Ken --
something you are prone to do fairly liberally. In your case, Ken, the
degree borders on psychosis, frankly. Ubfortunately Einstein's
assertions about the train observer violate the SR postulate that the
speed of light in the train is isotropic. Also they violate the SR
concept that relative motion and direction of relative motion will not
affect on the isotropy of the speed of light in the train. You are so
stupid. sigh

Ken Seto

Note that when it was posted on this newsgroup what Einstein
*actually* said, your reaction was priceless -- you said he didn't
understand relativity. So you are caught in a tight little circle. One
minute you believe he wrote what you dimly remember and so you cite
your belief as being what Einstein was trying to convey, and then when
you are shown what he actually wrote you no longer thing he meant what
he said.

The reason why Einstein said that the
train observer will not see these signals to occur simultaneously is
becasue the signal from the front is arriving at a transit time of L/(c
+v) and the signal from the rear is arriving at a transit time of L/(c-
v).

Note that the order of deduction is actually the reverse of this..
1. First, it is *observed* by the train observer that they arrive at
different times. No amount of telling him what he should have seen
instead will convince him otherwise, because he knows what he saw.

Hey idiot this is an assertion based on the validity of RoS.

No, it is not based on any assumption. It is an *observation*. What is
stipulated in Einstein's example is what the two observers *see* --
and that you will see if you manage to secure the book to reread the
passage.

We are
here tryin g to determine the validity of RoS.

2. The transit times are determined to be equal. This is because the
distance traveled is equal, as verified by the train observer, and
because the speed of light is equal in both directions, as verified by
the train observer.

The transit times are not equal if you include Einstein's assertion

...

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